The present invention relates to automatic transmission apparatus. More particularly, the present invention relates to hydraulic automatic transmission apparatus and to clutches.
Fluid couplers, such as torque converters, are used to convert the speed and torque output of a power source into a more usable speed and torque input for a work device. Many power sources convert one type of energy into an output of mechanical energy. For example, an internal combustion engine converts the energy stored in hydrocarbon fuel to rotational energy. Work devices typically use this mechanical energy to perform a useful function. For example, the tires of a vehicle use the rotational energy provided by the engine to propel the remainder of the vehicle. However, the output (speed and torque) provided by the power sources do not always match the input (speed and torque) required by the work device.
Because the output speeds and torques of the power sources often do not match the input speeds and torques required by the work devices, fluid couplers are provided to receive power from the power source at one speed and torque and to transfer this power to work devices at a different speed and torque as required by the work devices. Many fluid couplers have an input shaft and input blades that transfer the speed and torque supplied by the power source to a fluid. The power is then transferred through the fluid to output blades and an output shaft as the input to the work device. Thus, the input and output blades are able to rotate relative to one another at different speeds and torques so that the output from the power supply and the input to the work device can also rotate at different speeds and torques.
Hydraulic transmission apparatus are specific fluid couplers that are provided between power sources and work devices to convert the output of the power source into a more usable input for the work device. For example, a hydraulic vehicle transmission apparatus converts the relatively high rpm and low torque output of an internal combustion engine into a relatively low rpm and high torque input to the tires of a vehicle. This permits the tires to accelerate the vehicle relatively quickly from rest without overloading the available output torque of the engine. Furthermore, this enables coordination of the speed and torque output of the engine with the speed and torque requirements of the tires to facilitate smooth acceleration of the vehicle.
According to the present disclosure, a transmission apparatus configured to transmit energy from a power source to a work device is provided. The transmission apparatus includes an outer housing, input and output shafts, first and second pumps, first and second turbines, and a centrifugal clutch. The outer housing defines an interior region containing a fluid. The input shaft is configured to rotate about a first axis of rotation and is adapted to be coupled to the power source to receive energy therefrom. The output shaft is configured to rotate about a second axis of rotation and is adapted to be coupled to the work device to transmit energy thereto.
The first pump is positioned in the interior region of the outer housing and is coupled to rotate with the input shaft to input a first portion of the energy from the power source into the fluid contained in the interior region of the outer housing. The first turbine is positioned in the interior region of the outer housing between the first and second pumps. The first turbine is positioned to receive energy from the fluid contained in the interior region of the outer housing and to transmit said received energy to the output shaft.
The second pump is positioned in the interior region of the outer housing in a position spaced apart from the first pump between the first and second turbines. The second pump is coupled to rotate with the input shaft to input a second portion of the energy from the power source into the fluid contained in the interior region of the outer housing.
The second turbine is positioned in the interior region of the outer housing in a position spaced apart from the first turbine. The second turbine is positioned to receive energy from the fluid contained in the interior region of the outer housing and to transmit said received energy to the output shaft. The centrifugal clutch is configured to transfer energy from the input shaft to the output shaft.
According to another aspect of the present invention, a transmission apparatus is provided that is configured to transmit energy from a power source to a work device. The transmission apparatus includes input and output shafts, first and second stages of pump blades, a stage of turbine blades, and a coupler. The input shaft is adapted to receive energy from the power source. The output shaft is adapted to transmit energy to the work device. The first stage of pump blades is configured to transfer energy from the input shaft into a fluid. The second stage of pump blades is spaced apart from the first stage of pump blades and is configured to transfer energy from the input shaft into the fluid. The stage of turbine blades is configured to transfer energy from the fluid to the output shaft. The coupler is configured to directly couple the input shaft to the output shaft to transfer energy from the input shaft to the output shaft.
According to another aspect of the present invention, a transmission apparatus is provided that is configured to transfer energy from a power source to a work device. The transmission apparatus includes input and output shafts, fluid coupler, and a mechanical coupler. The input shaft is adapted to receive energy from the power source. The output shaft is adapted to transmit energy to the work device. The fluid coupler is configured to transfer energy from the input shaft to the output shaft. The mechanical coupler is configured to transfer energy from the input shaft to the output shaft simultaneous with the transfer of energy from the input shaft to the output shaft by the fluid coupler. The percentage of power transferred by the fluid coupler gradually decreasing and the percentage of power transferred by the mechanical coupler gradually increasing as the speed of the output shaft increases.
According to another aspect of the present invention, a transmission apparatus is provided that is configured to transmit energy from a power source to a work device. The transmission apparatus includes input and output shafts and a plurality of input and output blades. The input shaft is adapted to receive energy from the power source. The output shaft is adapted to transmit energy to the work device. The input blades are configured to transfer energy from the input shaft to a fluid. The plurality of output blades are configured to transfer energy from the fluid to the output shaft. The transmission apparatus further includes means for regulating the relative speed between the input and output blades to decrease to relative speed therebetween as the speed of the output shaft increases.
Additional features of the disclosure will become apparent to those skilled in the art upon consideration of the following detailed description when taken in conjunction with the accompanying drawings.